I've used AmmoSeek.com a few times when I was hunting for .223 Remington and some 9mm for range days. It was pretty convenient to have a site that aggregates prices from various retailers all in one place, which saved me some time comparing costs. Generally, the listings I found were accurate, but I always double-check the retailer's reputation before pulling the trigger, so to speak. I did run into a couple of sellers that seemed a bit sketchy and had unusual policies, so I'd advise sticking with well-known retailers whenever possible. Overall, it's a solid tool, just proceed with a bit of caution and do your homework on the sellers!